• DOI:10.1038/313050A0
• Corpus ID: 4257141

Rhodopsin-like sensitivity of extra-retinal photoreceptors mediating the photoperiodic response in quail

@article{Foster1985RhodopsinlikeSO,
  title={Rhodopsin-like sensitivity of extra-retinal photoreceptors mediating the photoperiodic response in quail},
  author={Russell G. Foster and Brian Keith Follett and John N. Lythgoe},
  journal={Nature},
  year={1985},
  volume={313},
  pages={50-52}
}

• R. Foster, B. Follett, J. Lythgoe
• Published 3 January 1985
• Biology
• Nature

It has been known for some 50 years that birds use photoreceptors in or near the hypothalamus to mediate the photoperiodic responses that control seasonal breeding1. So far, however, attempts to identify the photopigment by determining an action spectrum have failed1. The problems stem from the selective filtering of light by the tissues surrounding the photoreceptors and the need to deliver defined amounts of light over the days or weeks required to induce a quantitative measure of photostimulation. Here we have developed a technique which produces a quantitative action spectrum for the photoperiodic response in the Japanese quail; the results indicate the presence of a rhodopsin photopigment with a peak sensitivity of ∼492 nm. The photoreceptors exhibit a level of sensitivity comparable with that of vertebrate visual pigments. We conclude that the brain photoreceptors of birds are based on a rhodopsin/rhodopsin-like photopigment.